export function transListToTreeData(data, isFirst) {
    const result = [];
    for (const item of data) {
        if (isFirst && item.pid) {
            continue;
        }
        // 自己的id
        const id = item.id;
        // 去data中找有没有自己的孩子（_item.pid === id） >>> filter
        const children = this.departmentList.filter(d => d.pid === id);
        item.departments = dealData(children, false);
        result.push(item);
    }
    return result;
}